PICO Enables Two-Way Man-Machine Interaction

Digital interactive displays, which respond to human touch, have been evolving rapidly in the last few years. Dr. James Patten who works in the field of industrial design advanced the idea of interactive displays to a new level by developing a system that allows a two-way interaction between man and machine.

PICO flexible barrier

Physical Intervention in Computational Optimization or PICO for short is an interactive tabletop surface that can track the positions of specially tagged pucks on top of it. Using an array of electromagnets it can also move these pucks under software control. “We developed PICO to explore the idea of mechanical constraints as a new way to interact with computers during problem solving tasks” – says Patten.

The system can be used in complex problem solving tasks. A simple example demonstrated was its ability to maintain an equilateral triangle constructed of three pucks placed on the table. The user can change the location of one or more pucks and the computer will reposition the others so that they will still construct an equilateral triangle, while maintaining in the best way possible the precise location originally chosen by the user.

PICO uses the physics of the interaction between objects on the tabletop as a means to optimizing the software reaction’s to the user’s actions. The user can constrain the motion of any of the pucks using his hands or any other physical object, and the software will re-solve the optimization problem according to the new set of constraints.

An interesting example of a problem where this device can be used is demonstrated on Patton’s website: the computer is given a map of a specific area and a number of pucks. The user can associate each puck with a specific cellular telephone tower and place it at a desired location of the map projected on the table surface. The target is to maximize the overall network coverage by moving and reconfiguring the towers. The system supports zooming in and out of the map, preserving the original constraints. The computer then tries to place the pucks at the most optimized locations, as specified by the input of the problem. At all times the user is able to guide the optimization process by adding or removing mechanical constraints.

PICO ring

The user has many options he can use in order to refine the input of the task. For example, he can use a flexible barrier to limit the area in which the pucks can be located. He can also lock an object in place by holding it on the table, or by placing a weight on top of it, making it too heavy for the computer to move. A special roll of tape is used in order to allow a certain puck to move freely only in a specified area. A plastic collar placed around a puck ensures that it will always keep a certain minimum distance from any other puck. A ring placed around a group of pucks guarantees that the pucks will stay at a certain maximum distance from each other. The user can also specify the difficulty in moving a puck by either one of the following options: he can place a weight on the puck and so make it more difficult to move; an opposite effect can be obtained using a slippery surface (like Teflon), or simply by pouring some soap water on the surface. The variety of physical objects that can be used as mechanical constraints in PICO is quite large. As these constraints are added and taken away, the computer continues to optimize the overall layout of the cellular telephone towers. Patten says that the system is designed to balance the computer brute-force optimization with the user’s intuitive understanding of subtle issues that may be difficult to quantify. To date, PICO was used for factory floor layout planning, CNC tool-path optimization, and cellular telephone tower layout. Others see the future of PICO in various applications like gaming, art and so forth.

Sarah is a Computer Science and Business Management student at the Hebrew University in Jerusalem. Currently she is spending most of her time either at the university laboratories or tutoring at MEET - Middle East Education through Technology project, where she works as a programming instructor